One does not need to be a history buff or a culinary whiz to be skeptical of the claim's veracity. Anyone who has ever made vanilla dishes is probably aware that vanilla packs a lot of flavor into a relatively small bean and is rarely more visible than small dark specks in dishes such as crème brûlée.
Early images of ice cream are easy to find. The oldest we could dig up is from 1876:
Photographs from 1900, 1908, and 1909 showed similarly pale ice cream.
We found dozens of photographs of black ice cream, with or without a black cone. The photographs shared a common thread: attribution to New York City ice cream shop Morgenstern's, and their "coconut ash" flavor:
— 104.8 Channel 4 (@channel4dubai) May 30, 2016
We contacted a representative for Morgenstern's in 2017, who told us that the image indeed showed its "coconut ash" flavor and confirmed that they also sold black cones. In 2018, the New York City Department of Health issued a ban on usage of activated charcoal in foods. The flavor has since been removed from the menu.
So although the image of black ice cream was real, its backstory is not. Vanilla ice cream is naturally off-white, and the meme has no basis in fact.